JP7353200B2 - Film forming method - Google Patents

Description

The present disclosure relates to a film forming method.

Patent Document 1 discloses that a blocking layer composed of a self-assembled monolayer is formed on a gate dielectric layer, and then a first metal layer is formed on the gate dielectric layer by an atomic layer deposition (ALD) method. When depositing a first metal layer, the first metal layer is not formed over the gate dielectric layer in areas where there is a blocking layer, but is selectively deposited in areas where there is no blocking layer.

Special Publication No. 2007-533156

The present disclosure provides a technique that can enhance selectivity when selectively forming a metal oxide film in a desired region using a self-assembled film.

According to one aspect of the present disclosure, a step of preparing a substrate having a metal layer made of a first metal formed on a surface of a first region and an insulating layer formed on a surface of a second region; a step of supplying a raw material gas for a self-assembled film to form a self-assembled film on the surface of the metal layer; and after forming the self-assembled film, supplying a precursor gas containing a second metal. , supplying an oxidizing gas, and forming a second metal oxide film on the insulating layer by atomic layer deposition, after supplying the oxidizing gas and before supplying the precursor gas. There is provided a film forming method, comprising: supplying a reducing gas to reduce an oxide film of the first metal formed on a surface of the first metal.

According to one aspect, selectivity can be enhanced when a metal oxide film is selectively formed in a desired region using a self-assembled film.

1 is a flowchart illustrating an example of a film forming method according to an embodiment. 2 is a cross-sectional view showing an example of the state of a substrate in each step shown in FIG. 1. FIG. 2 is a cross-sectional view showing an example of the state of a substrate in each step shown in FIG. 1. FIG. FIG. 1 is a schematic diagram showing an example of a film forming system for implementing a film forming method according to an embodiment. 1 is a cross-sectional view showing an example of a processing device that can be used as a film forming device and a SAM forming device.

Hereinafter, embodiments for implementing the present disclosure will be described with reference to the drawings. Note that in this specification and the drawings, substantially the same configurations may be given the same reference numerals to omit redundant explanations. The following explanation will be made using the vertical direction or relationship in the drawings, but this does not represent a universal vertical direction or relationship.

<Embodiment>
FIG. 1 is a flowchart illustrating an example of a film forming method according to an embodiment. 2 and 3 are cross-sectional views showing an example of the state of the substrate in each step shown in FIG. 1. 2(A) to 2(E) show states of the substrate 10 corresponding to steps S101 to S105 shown in FIG. 1, respectively. 3(A) to 3(D) show the states of the substrate 10 corresponding to steps S104A to S104C shown in FIG. 1, and the substrate 10 shown in FIG. 2(C) to the substrate 10 shown in FIG. shows the details of the state change.

The film forming method includes step S101 of preparing the substrate 10 as shown in FIG. 2(A). Preparing includes, for example, carrying the substrate 10 into a processing container (chamber) of a film forming apparatus. The substrate 10 includes a conductive film 11, a natural oxide film 11A, an insulating film 12, and a base substrate 15.

The conductive film 11 and the insulating film 12 are provided on one surface of the base substrate 15 (the upper surface in FIG. 2(A)), and the conductive film 11 is provided with a natural surface on one surface (the upper surface in FIG. 2(A)). An oxide film 11A is provided. In FIG. 2A, the native oxide film 11A and the insulating film 12 are exposed on the surface of the substrate 10.

The substrate 10 has a first area A1 and a second area A2. Here, as an example, the first area A1 and the second area A2 are adjacent to each other in plan view. The conductive film 11 is provided on the upper surface side of the base substrate 15 within the first region A1, and the insulating film 12 is provided on the upper surface side of the base substrate 15 within the second region A2. The natural oxide film 11A is provided on the upper surface of the conductive film 11 within the first region A1.

Although the number of first areas A1 is one in FIG. 2(A), it may be plural. For example, two first areas A1 may be arranged with a second area A2 in between. Similarly, although the number of second regions A2 is one in FIG. 2(A), it may be plural. For example, two second areas A2 may be arranged to sandwich the first area A1.

Note that although only the first area A1 and the second area A2 exist in FIG. 2(A), a third area may further exist. The third region is a region where a layer made of a different material from the conductive film 11 in the first region A1 and the insulating film 12 in the second region A2 is exposed. The third area may be placed between the first area A1 and the second area A2, or may be placed outside the first area A1 and the second area A2.

The conductive film 11 is an example of a metal layer made of a first metal. The first metal is, for example, a metal such as copper (Cu), cobalt (Co), tungsten (W), or ruthenium (Ru). The surfaces of these metals naturally oxidize over time in the atmosphere. The oxide is the natural oxide film 11A. The natural oxide film 11A can be removed by reduction treatment.

Here, as an example, a mode will be described in which the conductive film 11 is made of copper (Cu) and the natural oxide film 11A is copper oxide formed by natural oxidation. Copper oxide as the natural oxide film 11A may contain CuO and Cu ₂ O.

The insulating film 12 is an example of an insulating layer. The insulating layer is, for example, an insulating material containing silicon (Si), such as silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbonide, or silicon oxycarbonitride. Hereinafter, silicon oxide will also be referred to as SiO, regardless of the composition ratio of oxygen and silicon. Similarly, silicon nitride is also written as SiN, silicon oxynitride is also written as SiON, silicon carbide is also written as SiC, silicon oxycarbide is also written as SiOC, and silicon oxycarbonitride is also written as SiOCN. The insulating layer is SiO in this embodiment.

The base substrate 15 is, for example, a semiconductor substrate such as a silicon wafer. The substrate 10 may further include a base film formed of a material different from the base substrate 15 and the conductive film 11 between the base substrate 15 and the conductive film 11. Similarly, the substrate 10 may further include a base film formed of a material different from the base substrate 15 and the insulating film 12 between the base substrate 15 and the insulating film 12.

Such a base film may be, for example, a SiN layer. The SiN layer or the like may be, for example, an etch stop layer that stops etching.

The film forming method includes step S102 of manufacturing the substrate 10 shown in FIG. 2(B) by reducing the natural oxide film 11A (see FIG. 2(A)). To reduce the natural oxide film 11A, for example, the flow rates of hydrogen (H ₂ ) and argon (Ar) in the processing container of the film forming apparatus are set to 100 sccm and 2500 sccm, respectively, and the pressure in the processing container is adjusted to 1 torr to 10 torr ( 133.32Pa to 1333.22Pa). Then, in a hydrogen atmosphere in which hydrogen is less than 0.5% of the atmospheric gas in the processing container, the susceptor is heated so that the temperature of the substrate 10 is 150° C. to 200° C.

In step S102, the copper oxide as the natural oxide film 11A is reduced to Cu and removed. As a result, as shown in FIG. 2(B), a substrate 10 including a conductive film 11, an insulating film 12, and a base substrate 15 is obtained. On the surface of the first region A1 of the substrate 10, Cu as the conductive film 11 is exposed. Note that the reduction treatment of the natural oxide film 11A may be a reduction treatment using hydrogen (H ₂ ) plasma. Further, the reduction treatment of the natural oxide film 11A is not limited to a dry process, but may be a wet process using alcohol such as isopropyl alcohol (IPA), for example. Further, the reduction treatment of the natural oxide film 11A may be a process using organic molecules containing oxygen. Further, the reduction treatment of the natural oxide film 11A may be a heat treatment such as FGA (Forming Gas Anneal). FGA is a heat treatment in which, for example, the substrate 10 is heated to approximately 300° C. to 450° C. and nitrogen gas mixed with a trace amount of hydrogen is flowed into the processing container to reduce the natural oxide film 11A.

The film forming method includes a step S103 of forming a SAM (Self-Assembled Monolayer) 13, as shown in FIG. 2(C). The SAM 13 is not formed in the second region A2. The SAM 13 is an example of a self-organized film.

The organic compound for forming SAM13 may have any fluorocarbon (CFx) or alkyl (CHx) functional group as long as it is thiol-based; for example, CH3(CH2)[x]CH2SH [x=1~18], CF3(CF2)[x]CH2CH2SH [x=0~18] is sufficient. Fluorocarbons (CFx) also include fluorobenzenethiol.

For example, the flow rates of a gaseous thiol-based organic compound and argon (Ar) are set to 100 sccm and 1500 sccm, respectively, and the pressure in the processing container of the film forming apparatus is set to 1 torr to 10 torr (133.32 Pa to 1333.22 Pa). Then, the susceptor is heated so that the temperature of the substrate 10 is 150° C. to 200° C.

The above-mentioned thiol-based organic compounds are compounds that easily exchange electrons with metal oxides. Therefore, the SAM 13 has a property of adsorbing to the surface of the conductive film 11 and not adsorbing to the surface of the insulating film 12 where electron transfer is difficult to occur. Therefore, the SAM 13 is selectively formed on the surface of the conductive film 11.

In step S103, the SAM 13 is formed on the surface of the conductive film 11, and as shown in FIG. 2(C), the substrate 10 is formed with the conductive film 11 and the SAM 13 in the first region A1, and the insulating film 12 in the second region A2. is obtained. In FIG. 2C, the SAM 13 and the insulating film 12 are exposed on the surface of the substrate 10. Step S103 utilizes the selectivity of thiol-based organic compounds to form SAM13.

As shown in FIG. 2(D), a second film is selectively deposited on the surface of the substrate 10 shown in FIG. The step S104 includes forming an AlO film 14 as a second metal oxide film on the surface of the insulating film 12 in the region A2. Since the SAM 13 inhibits the formation of the AlO film 14, the AlO film 14 is selectively formed in the second region A2. An AlO film 14, which is an insulating film, can be further selectively laminated on the insulating film 12 originally existing in the second region A2. Note that when a third region exists in addition to the first region A1 and the second region A2, the AlO film 14 may or may not be formed in the third region.

The AlO film 14 may include oxidized aluminum having a composition other than aluminum oxide Al ₂ O ₃ (alumina). That is, herein, it is also expressed as AlO regardless of the composition ratio of aluminum and oxygen. Details of the process of forming such an AlO film 14 will be described later using FIG. 3.

The film forming method includes a step S105 of removing the SAM 13 (see FIG. 2(D)), as shown in FIG. 2(E). The SAM 13 may be removed by, for example, treatment using plasma. Examples of plasma generation mechanisms used in the process for removing SAM13 include capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and microwave plasma (MWP). etc., and any plasma generation mechanism capable of generating radicals may be used. In addition, the plasma generation mechanism may be integrated into the processing container, or the plasma generation mechanism may be provided separately from the processing container, and the plasma generation gas may be converted into plasma outside the processing container before being introduced into the processing container. A device may also be used.

Next, details of step S104 of forming the AlO film 14 will be explained.

In the step of forming the AlO film 14 by the ALD method, first, as shown in FIG. 3(A), a source gas of TMA (trimethylaluminum) is supplied to form the AlO film 14 on the substrate 10 shown in FIG. 2(C). This step includes a step S104A of adsorbing the TMA film 14A to the second area A2. When step S104A is performed first, the TMA film 14A is adsorbed onto the surface of the insulating film 12 in the second region A2, as shown in FIG. 3(A).

TMA is an organic aluminum compound and is a precursor for producing the AlO film 14. That is, the raw material gas for TMA is a precursor gas. The raw material gas for TMA has the property of adsorbing on hydroxyl groups (OH groups).

Here, hydroxy groups exist on the surface of SiO of the insulating film 12. Further, SAM13 exhibits high orientation due to intermolecular van der Waals forces, tends to be oriented obliquely to the surface of the film, and has gaps between molecules. There is a possibility that the raw material gas of TMA may enter into such a gap, but since the surface of the conductive film 11 has been reduced in the process shown in FIG. 2(B), there are no hydroxyl groups on the surface of the conductive film 11. .

Therefore, the source gas of TMA is selectively adsorbed to the hydroxy groups on the surface of SiO of the insulating film 12. In addition, in the step of supplying the TMA raw material gas, for example, the flow rate of the TMA raw material gas is set to 20 sccm to 200 sccm, and the pressure in the processing container of the film forming apparatus is set to 0.1 torr to 10 torr (13.332 Pa to 1333 torr). .22Pa). Further, the susceptor is heated so that the temperature of the substrate 10 is 100° C. to 200° C.

In the step of forming the AlO film 14 using the ALD method, H ₂ O (steam) is flowed as a reactant (reactant (here, oxidizing agent)) into the processing container to oxidize the TMA film 14A, as shown in FIG. 3(B). ), it includes step S104B of manufacturing the AlO film 14B. H ₂ O (water vapor) is an example of an oxidizing gas. Note that the oxidizing agent may be a gas such as oxygen (O ₂ ), ozone (O ₃ ), or hydrogen peroxide (H ₂ O ₂ ), and may be supplied as remote plasma.

In the step of oxidizing the TMA film 14A to produce the AlO film 14B, for example, the flow rate of H ₂ O is set to 50 sccm to 300 sccm, and the pressure in the processing chamber of the film forming apparatus is set to 0.1 torr to 10 torr (13. 332 Pa to 1333.22 Pa).

If steps S104A and S104B are performed once each, an AlO film 14B having a thickness of about 0.1 μm is obtained, for example. Therefore, by repeating steps S104A and S104B, for example, an AlO film 14 having a thickness of about 1 μm to 10 μm (see FIG. 2(D)) can be obtained. Note that when repeating steps S104A and S104B, the processing container may be purged between steps S104A and S104B.

When steps S104A and S104B are performed once to obtain an AlO film 14B having a thickness of 0.1 μm, steps S104A and S104B may be repeated 10 times to obtain an AlO film 14 having a thickness of 1 μm. Further, in this case, in order to obtain the AlO film 14 having a film thickness of 10 μm, steps S104A and S104B may be repeated 100 times. The number of repetitions of steps S104A and S104B may be set depending on the desired thickness of the AlO film 14.

Moreover, when H ₂ O (water vapor) is flowed into the processing container to oxidize the TMA film 14A to produce the AlO film 14B in step S104B, as shown in FIG. 3(B), on the surface of the conductive film 11, An oxide film 11B may be formed. That is, H ₂ O (water vapor) may reach the surface of the conductive film 11 (Cu film) through the gaps between the molecules of the SAM 13, and an oxide film 11B made of CuO may be formed on the surface of the conductive film 11. .

Since hydroxy groups exist on the surface of such an oxide film 11B, if step S104A is performed with the oxide film 11B formed on the surface of the conductive film 11 in step S104B, the source gas of TMA will be transferred to the insulating film. 12 and the surface of the oxide film 11B. In such a case, the TMA film 14A cannot be selectively adsorbed onto the surface of the insulating film 12 in step S104A.

Therefore, in the step of forming the AlO film 14 by the ALD method, after step S104B, as shown in FIG. It includes step S104C of reducing (CuO) to Cu. Since the IPA gas passes through the gaps between molecules of the SAM 13 and reaches the oxide film 11B on the surface of the conductive film 11, the oxide film 11B can be reduced. If step S104A is performed after step S104C, the TMA film 14A can be selectively adsorbed onto the surface of the second region A2 of the substrate 10.

In step S104C, the flow rate of the IPA gas may be set to 20 sccm to 200 sccm, and the pressure within the processing container of the film forming apparatus may be set to 0.1 torr to 10 torr (13.332 Pa to 1333.22 Pa).

Note that in step S104C shown in FIG. 3C, the AlO film 14B is hardly reduced, so the AlO film 14B remains after completing step S104C.

If the surface of the conductive film 11 is reduced in step S104C in this way, TMA will not be adsorbed on the surface of the conductive film 11 even if step S104A is subsequently performed again and the TMA source gas is supplied to the processing container. As shown in FIG. 3(D), the TMA film 14C can be selectively adsorbed onto the AlO film 14B. Note that when reducing the surface of the conductive film 11 in step S104C, the surface of the conductive film 11 may be reduced by supplying hydrogen (H ₂ ) gas instead of IPA gas as the reducing gas.

Similar to FIG. 3A, FIG. 3D shows a step S104A of supplying TMA source gas to the substrate 10. FIG. 3(A) shows step S104A in which the TMA film 14A is first formed on the surface of the insulating film 12, and FIG. 3(D) shows step S104A in the second and subsequent steps when repeating steps S104A and S104B. Step S104A is shown in which a TMA film 14C is formed on the AlO film 14B.

Here, step S104C of reducing the oxide film 11B shown in FIG. 3(C) may be performed every time after step S104B when steps S104A and S104B are repeatedly performed, or steps S104A and S104B may be repeated multiple times. It may also be performed after step S104B. In the latter case, every time steps S104A and S104B are repeated multiple times, step S104C is performed once after step S104B. Step S104C is a step of reducing the oxide film 11B (CuO) that may be formed in step S104B to Cu, so it may be performed after step S104B.

Further, in the case where the oxide film 11B (CuO) is formed in step S104B as shown in FIG. There is a risk that the TMA film will be adsorbed onto the surface.

In such a case, even if the reduction step of step S104C is performed, it is almost impossible to reduce the TMA film adsorbed on the oxide film 11B. This is because the reduction step using IPA gas, such as step S104C, does not have enough reducing power to reduce the TMA film.

Therefore, if step S104C is to be performed once after step S104B every time steps S104A and S104B are repeated multiple times, step S104C may be performed before the TMA film is adsorbed onto the oxide film 11B. That is, step S104C may be performed while the oxide film 11B (CuO) can be reduced and restored to the conductive film 11 (Cu). The number of repetitions may be determined in advance through experiments or the like.

Note that the steps shown in FIGS. 3(A) to 3(D) may be divided into one or more steps and performed in different processing vessels for each group, but the processing for reducing the oxide film 11B It is also preferable to carry out the process in one processing vessel from the viewpoint of continuously supplying the raw material gas of TMA to the processing vessel.

In addition, here, the step of forming the AlO film 14 by the ALD method starts from step S104A of adsorbing the TMA source gas onto the surface of the insulating film 12 to form the TMA film 14A, as shown in FIG. 3(A). The starting form will be described, but before step S104A, a step of reducing the surface of the conductive film 11 may be performed as in step S104C.

As described above, while repeatedly performing steps S104A and S104B, when the number of repetitions reaches a predetermined number (one or more times), step S104C is performed after step S104B. An AlO film 14 shown in can be manufactured.

At this time, by performing step S104C after step S104B, even if the oxide film 11B (see FIG. 3B) is formed on the surface of the conductive film 11, it can be reduced in step S104C. Therefore, when performing step S104A as shown in FIG. 3(D) thereafter, the selectivity for selectively adsorbing the TMA film 14C to the second region A2 can be enhanced. The TMA film 14C is then oxidized to become the AlO film 14B (see FIG. 3C) in step S104B shown in FIG. (C)) becomes thicker, and the AlO film 14 shown in FIG. 2(D) is obtained. In this way, by performing step S104C after step S104B, it is possible to enhance the selectivity when selectively forming the AlO film 14 in the second region A2.

Therefore, it is possible to provide a film forming method that can enhance the selectivity when selectively forming the AlO film 14 in a desired region using the SAM 13.

In addition, although the embodiment in which the AlO film 14 is formed as a second metal oxide film on the insulating film 12 in the second region A2 has been described above, instead of the AlO film 14, hafnia (HfO ₂ ) or zirconia may be used. (ZrO ₂ ) may be formed.

When forming a hafnia (hafnium oxide/HfO ₂ ) film, the precursor gas containing the second metal is tetrakis(dimethylamino)hafnium, tetrakis(diethylamino)hafnium, or tetrakis(ethylmethylamino)hafnium. You can use When forming a zirconia (zirconium dioxide/ZrO ₂ ) film, tetrakis(dimethylamino)zirconium, tetrakis(diethylamino)zirconium, or tetrakis(ethylmethylamino)zirconium is used as the precursor gas containing the second metal. You can use

In addition, since the selectivity when selectively forming the AlO film 14 in the second region A2 can be enhanced, throughput can be improved, and a film formation method that realizes a highly productive semiconductor manufacturing process can be developed. can be provided.

In addition, although the embodiment in which all the processes from Step S101 to Step S105 are performed in the same processing container has been described above, the reduction treatment in Step S102, the SAM 13 formation treatment in Step S103, the AlO film formation in Step S104, and the All of the SAM 13 removal processing in S105 may be performed in different processing containers of the film forming apparatus. For example, it is useful when it is desired to independently set processing conditions such as heating temperature in each step.

In addition, the SAM 13 formation process in step S103 and the SAM 13 removal process in step S105 are performed in the same processing container, and the reduction process in step S102 and the AlO film formation in step S104 are performed in different processing containers. You can also do this. For example, this is useful when the reduction treatment in step S102 is performed in a wet process. Further, it is useful when it is desired to perform the AlO film formation in step S104 in an independent processing container. Further, if the reduction treatment in step S102 and the reduction treatment in step S104C are the same treatment, the reduction treatment in step S102 and the AlO film formation in step S104 may be performed in the same processing container. .

Note that the preparation in step S101 and the reduction treatment in step S102 are performed in the same processing container.

<Film forming system>
Next, a system for implementing a film forming method according to an embodiment of the present disclosure will be described.

The film forming method according to an embodiment of the present disclosure may be in any form of a batch device, a single wafer device, or a semi-batch device. However, the optimum temperature may differ in each of the above steps, and when the surface of the substrate is oxidized and the surface state changes, it may be difficult to carry out each step. Taking these points into consideration, a multi-chamber type single-wafer film forming system is preferred because it allows each step to be easily set at an optimal temperature and all steps can be performed in a vacuum.

Hereinafter, such a multi-chamber type single wafer deposition system will be explained.

FIG. 4 is a schematic diagram showing an example of a film forming system for carrying out a film forming method according to an embodiment. Here, unless otherwise specified, a case will be described in which processing is performed on the substrate 10.

As shown in FIG. 4, the film forming system 100 includes a redox processing apparatus 200, a SAM forming apparatus 300, a film forming apparatus 400, and a plasma processing apparatus 500. These devices are connected to four walls of the vacuum transfer chamber 101, which has a heptagonal planar shape, via gate valves G, respectively. The inside of the vacuum transfer chamber 101 is evacuated by a vacuum pump and maintained at a predetermined degree of vacuum. That is, the film forming system 100 is a multi-chamber type vacuum processing system, and is capable of continuously performing the above-described film forming method without breaking the vacuum.

The redox processing apparatus 200 is, for example, a processing apparatus that performs a reduction process on the substrate 10 (see FIG. 2(A)).

The SAM forming apparatus 300 is, for example, an apparatus that selectively forms the SAM 13 on the substrate 10 (see FIG. 2C) by supplying a thiol-based organic compound gas.

The film forming apparatus 400 is, for example, an apparatus that forms the AlO film 14 on the substrate 10 (see FIG. 2(D)) by an ALD method.

The plasma processing apparatus 500 is for performing a process of etching and removing the SAM 13, for example.

Three load lock chambers 102 are connected to the other three walls of the vacuum transfer chamber 101 via gate valves G1. An atmospheric transfer chamber 103 is provided on the opposite side of the vacuum transfer chamber 101 with the load lock chamber 102 in between. The three load lock chambers 102 are connected to an atmospheric transfer chamber 103 via a gate valve G2. The load lock chamber 102 is provided to control the pressure between atmospheric pressure and vacuum when the substrate 10 is transferred between the atmospheric transfer chamber 103 and the vacuum transfer chamber 101.

A wall of the atmospheric transfer chamber 103 opposite to the mounting wall of the load lock chamber 102 has three carrier mounting ports 105 for mounting carriers (FOUPs, etc.) C for accommodating the substrates 10. Further, an alignment chamber 104 for aligning the substrate 10 is provided on a side wall of the atmospheric transfer chamber 103. A downflow of clean air is formed in the atmospheric transfer chamber 103.

A first transport mechanism 106 is provided within the vacuum transport chamber 101 . The first transport mechanism 106 transports the substrate 10 to the redox processing apparatus 200, the SAM forming apparatus 300, the film forming apparatus 400, the plasma processing apparatus 500, and the load lock chamber 102. The first transport mechanism 106 has two independently movable transport arms 107a and 107b.

A second transport mechanism 108 is provided within the atmospheric transport chamber 103 . The second transport mechanism 108 transports the substrate 10 to the carrier C, the load lock chamber 102, and the alignment chamber 104.

The film forming system 100 has an overall control section 110. The overall control unit 110 includes a main control unit including a CPU (computer), an input device (keyboard, mouse, etc.), an output device (printer etc.), a display device (display etc.), and a storage device (storage medium). have. The main control unit controls each component of the redox processing apparatus 200, the SAM forming apparatus 300, the film forming apparatus 400, the plasma processing apparatus 500, the vacuum transfer chamber 101, and the load lock chamber 102. The main control unit of the overall control unit 110 controls the film forming system 100 to perform the film forming process according to the embodiment based on, for example, a processing recipe stored in a storage medium built into the storage device or a storage medium set in the storage device. Execute the action to perform the membrane method. Note that each device may be provided with a lower-level control section, and the overall control section 110 may be configured as a higher-level control section.

In the film forming system configured as described above, the substrate 10 is taken out from the carrier C connected to the atmospheric transport chamber 103 by the second transport mechanism 108, and after passing through the alignment chamber 104, it is transferred to one of the load lock chambers. 102. After evacuating the inside of the load lock chamber 102, the substrate 10 is transported to the redox processing apparatus 200, the SAM forming apparatus 300, the film forming apparatus 400, and the plasma processing apparatus 500 by the first transport mechanism 106. , performs the film forming process of the embodiment. Thereafter, the SAM 13 is removed by etching using the plasma processing apparatus 500, if necessary.

After the above processing is completed, the first transport mechanism 106 transports the substrate 10 to one of the load lock chambers 102, and the second transport mechanism 108 returns the substrate 10 in the load lock chamber 102 to the carrier C.

The above-described processing is performed simultaneously on a plurality of substrates 10, and selective film formation processing on a predetermined number of substrates 10 is completed.

Since each of these processes is performed using independent single-wafer equipment, it is easy to set the optimum temperature for each process, and a series of processes can be performed without breaking the vacuum, which helps to suppress oxidation during the process. can.

<Example of film forming process and SAM forming apparatus>
Next, an example of a film forming apparatus such as the oxidation-reduction processing apparatus 200, the film forming apparatus 400, and the SAM forming apparatus 300 will be described.

FIG. 5 is a cross-sectional view showing an example of a processing apparatus that can be used as a film forming apparatus and a SAM forming apparatus.

The oxidation-reduction processing apparatus 200, the film forming apparatus 400, and the SAM forming apparatus 300 may have similar configurations, and may be configured as a processing apparatus 600 as shown in FIG. 5, for example.

The processing apparatus 600 has a substantially cylindrical processing container (chamber) 601 that is configured to be airtight, and a susceptor 602 for horizontally supporting the substrate 10 is located in the center of the bottom wall of the processing container 601. It is supported by a cylindrical support member 603 provided in the. A heater 605 is embedded in the susceptor 602, and this heater 605 heats the substrate 10 to a predetermined temperature by being supplied with power from a heater power source 606. Note that the susceptor 602 is provided with a plurality of lifting pins (not shown) for supporting and raising/lowering the substrate 10 so as to be projectable and retractable from the surface of the susceptor 602 .

A shower head 610 is provided on the ceiling wall of the processing container 601 to face the susceptor 602 for introducing a processing gas for film formation or SAM formation into the processing container 601 in a shower-like manner. The shower head 610 is for discharging gas supplied from a gas supply mechanism 630, which will be described later, into the processing container 601, and has a gas introduction port 611 formed in its upper part for introducing the gas. Further, a gas diffusion space 612 is formed inside the shower head 610, and a large number of gas discharge holes 613 communicating with the gas diffusion space 612 are formed on the bottom surface of the shower head 610.

The bottom wall of the processing container 601 is provided with an exhaust chamber 621 that projects downward. An exhaust pipe 622 is connected to the side surface of the exhaust chamber 621, and an exhaust device 623 having a vacuum pump, a pressure control valve, etc. is connected to the exhaust pipe 622. By operating this exhaust device 623, it is possible to bring the inside of the processing container 601 into a predetermined reduced pressure (vacuum) state.

A loading/unloading port 627 for loading/unloading the substrate 10 to/from the vacuum transfer chamber 101 is provided on the side wall of the processing container 601, and the loading/unloading port 627 is opened/closed by a gate valve G.

The gas supply mechanism 630 includes a gas supply source necessary for forming the AlO film 14 or the SAM 13, individual piping for supplying gas from each supply source, on-off valves provided in the individual piping, and gas flow rate control. It has a flow rate controller such as a mass flow controller that performs this, and further has a gas supply pipe 635 that guides gas from the individual pipes to the shower head 610 via the gas inlet 611.

The gas supply mechanism 630 supplies an organic compound raw material gas and a reaction gas to the shower head 610 when the processing apparatus 600 performs ALD film formation of the AlO film 14 . Further, when the processing apparatus 600 forms a SAM, the gas supply mechanism 630 supplies vapor of a compound for forming the SAM into the processing container 601. Further, the gas supply mechanism 630 is configured to be able to also supply an inert gas such as N ₂ gas or Ar gas as a purge gas or heat transfer gas.

In the processing apparatus 600 configured as described above, the gate valve G is opened, the substrate 10 is carried into the processing container 601 from the carry-in/out port 627, and placed on the susceptor 602. The susceptor 602 is heated to a predetermined temperature by a heater 605, and the substrate 10 is heated by introducing an inert gas into the processing container 601. Then, the inside of the processing container 601 is evacuated by the vacuum pump of the exhaust device 623, and the pressure inside the processing container 601 is adjusted to a predetermined pressure.

Next, when the processing apparatus 600 performs ALD deposition of the AlO film 14, the organic compound source gas and the reaction gas are alternately supplied into the processing container 601 from the gas supply mechanism 630 with a purge in the processing container 601 in between. . Further, when the processing apparatus 600 forms a SAM, the gas supply mechanism 630 supplies vapor of an organic compound for forming the SAM into the processing container 601 .

Although the embodiments of the film forming method according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments and the like. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These naturally fall within the technical scope of the present disclosure.

10 Substrate 11 Conductive film 11A Natural oxide film 12 Insulating film 13 SAM
14 AlO film 15 Base substrate

Claims (15)

preparing a substrate having a first metal layer formed on the surface of the first region and an insulating layer formed on the surface of the second region;
supplying a raw material gas for the self-assembled film to form a self-assembled film on the surface of the metal layer;
After forming the self-assembled film, the supply of the precursor gas containing the second metal and the supply of the oxidizing gas are repeated multiple times to deposit the second metal on the insulating layer by atomic layer deposition. a step of forming an oxide film;
Every time the supply of the precursor gas and the supply of the oxidizing gas are repeated, a reducing gas is supplied after the supply of the oxidizing gas and before the supply of the precursor gas to reduce the amount of the first metal. and reducing an oxide film of the first metal formed on the surface. The step of reducing the oxide film of the first metal includes supplying the precursor gas after supplying the oxidizing gas when supplying the precursor gas and supplying the oxidizing gas are repeated multiple times. The film forming method according to claim 1, which is a step performed before. Before the step of forming the self-organized film, further comprising a step of supplying a reducing gas to the substrate to reduce the natural oxide film of the first metal formed on the surface of the first metal. The film forming method according to claim 1 or 2, comprising: The reducing agent used in the step of reducing the natural oxide film is hydrogen (H ₂ ) gas, hydrogen (H ₂ 4. The film forming method according to claim 3, wherein the film forming method is plasma or organic molecules containing oxygen. 5. The film forming method according to claim 4, wherein the oxygen-containing organic molecule is alcohol. 6. The film forming method according to claim 5, wherein the alcohol is isopropyl alcohol (IPA). 7. The film forming method according to claim 1, wherein the second metal is aluminum (Al), hafnium (Hf), or zirconium (Zr). 8. The film forming method according to claim 7 , wherein the second metal is aluminum (Al) and the precursor gas is trimethylaluminum. 8. The second metal is hafnium (Hf), and the precursor gas is tetrakis(dimethylamino)hafnium, tetrakis(diethylamino)hafnium, or tetrakis(ethylmethylamino)hafnium. Film formation method. 8. The second metal is zirconium (Zr), and the precursor gas is tetrakis(dimethylamino)zirconium, tetrakis(diethylamino)zirconium, or tetrakis(ethylmethylamino)zirconium. Film formation method. The oxidizing gas according to any one of claims 1 to 10 , wherein the oxidizing gas is water vapor (H ₂ O), hydrogen peroxide (H ₂ O ₂ ), oxygen (O ₂ ), or ozone (O ₃ ). Film formation method. The film forming method according to any one of claims 1 to 11 , wherein the reducing gas is alcohol or hydrogen ( _H2 ). 13. The film forming method according to claim 12 , wherein the alcohol of the reducing gas is isopropyl alcohol (IPA). 14. The film forming method according to claim 1, wherein the source gas for the self-assembled film is a thiol-based source gas for the self-assembled film. The film forming method according to any one of claims 1 to 14 , further comprising the step of removing the self-organized film from the surface of the metal layer after the step of forming the second metal oxide film. .

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